Cervical lymph node metastasis prediction from papillary thyroid carcinoma US videos: a prospective multicenter study.

BACKGROUND: Prediction of lymph node metastasis (LNM) is critical for individualized management of papillary thyroid carcinoma (PTC) patients to avoid unnecessary overtreatment as well as undesired under-treatment. Artificial intelligence (AI) trained by thyroid ultrasound (US) may improve prediction performance. METHODS: From September 2017 to December 2018, patients with suspicious PTC from the first medical center of the Chinese PLA general hospital were retrospectively enrolled to pre-train the multi-scale, multi-frame, and dual-direction deep learning (MMD-DL) model. From January 2019 to July 2021, PTC patients from four different centers were prospectively enrolled to fine-tune and independently validate MMD-DL. Its diagnostic performance and auxiliary effect on radiologists were analyzed in terms of receiver operating characteristic (ROC) curves, areas under the ROC curve (AUC), accuracy, sensitivity, and specificity. RESULTS: In total, 488 PTC patients were enrolled in the pre-training cohort, and 218 PTC patients were included for model fine-tuning (n = 109), internal test (n = 39), and external validation (n = 70). Diagnostic performances of MMD-DL achieved AUCs of 0.85 (95% CI: 0.73, 0.97) and 0.81 (95% CI: 0.73, 0.89) in the test and validation cohorts, respectively, and US radiologists significantly improved their average diagnostic accuracy (57% vs. 60%, P = 0.001) and sensitivity (62% vs. 65%, P < 0.001) by using the AI model for assistance. CONCLUSIONS: The AI model using US videos can provide accurate and reproducible prediction of cervical lymph node metastasis in papillary thyroid carcinoma patients preoperatively, and it can be used as an effective assisting tool to improve diagnostic performance of US radiologists. TRIAL REGISTRATION: We registered on the Chinese Clinical Trial Registry website with the number ChiCTR1900025592.

Follow-up strategy of radiofrequency ablation for papillary thyroid microcarcinoma: defining a response-to-ablation system.

OBJECTIVE: To define a response-to-ablation system based on dynamic risk stratification proposed by the 2015 American Thyroid Association guidelines for predicting clinical outcomes and guiding follow-up strategies for patients with low-risk papillary thyroid microcarcinoma (PTMC) who underwent radiofrequency ablation (RFA). METHODS: This retrospective study reviewed patients with low-risk PTMC who underwent RFA between 2014 and 2018. We classified patients into three groups based on their response to therapy at the 1-year follow-up: complete, indeterminate, and incomplete. The primary endpoints were local tumor progression (LTP) and disease-free survival (DFS). RESULTS: Among the 748 patients (mean age, 43.7 years ± 9.8; 586 women), 4.0% (30/748) had LTP during a median follow-up of 5 years. The response was complete in 80.2% (600/748) of the patients, indeterminate in 18.1% (135/748), and incomplete in 1.7% (13/748). The LTP rate in the final follow-up was 1% (6/600), 8.1% (11/135), and 100% (13/13), respectively. The risk of LTP was significantly different in the incomplete response group (HR, 1825.82; 95% CI: 458.27, 7274.36; p < 0.001) and indeterminate response group (HR, 8.12; 95% CI: 2.99, 22.09; p < 0.001) than in the complete response group. There were significant differences in DFS among groups (p < 0.001). The proportion of variation explained and C-index of the system was high (27.66% and 0.79, respectively). CONCLUSIONS: We defined a response-to-ablation system that provides a new paradigm for the management of patients with PTMC who underwent RFA. Our data confirm that the system can effectively predict the risk of LTP and guide ongoing follow-up recommendations. KEY POINTS: • The response-to-ablation system can classify patients with low-risk PTMC who underwent RFA into complete, indeterminate, or incomplete response categories. • Results suggest that, in this population, this system can identify three separate cohorts of patients who have significantly different clinical outcomes. • The response-to-ablation system will help better tailor the ongoing follow-up recommendations.

Radiofrequency ablation for capsular-located versus noncapsular-located papillary thyroid microcarcinoma: a propensity score matching study of 1095 patients.

OBJECTIVES: To assess the safety and efficacy of radiofrequency ablation (RFA) for capsular-located papillary thyroid microcarcinoma (PTMC) in a large cohort and to compare its outcomes with those of noncapsular-located PTMC. METHODS: We retrospectively reviewed patients who underwent RFA for solitary capsular-located and noncapsular-located low-risk PTMC (n = 1095) from June 2014 to October 2020. To balance confounding variables between capsular and noncapsular groups, we employed the 1:1 propensity score matching approach. We evaluated and compared tumor changes, disease progression, and complications in both groups. Furthermore, we analyzed the association between capsular location and disease progression using multivariable Cox regression. RESULTS: During a mean follow-up time of 29.86 ± 16.14 months and 29.73 ± 15.69 months, no substantial difference was observed between capsular and noncapsular groups in the latest volume (0.83 ± 3.66 mm3 vs. 0.85 ± 3.67 mm3, p = 0.44) and volume reduction ratio (99.29 ± 4.04% vs. 99.43 ± 3.03%, p = 0.43), and cumulative disappearance rate (87.87% vs. 86.07%, p = 0.31). In addition, no significant differences were observed in complication incidence (1.35% vs. 1.12%, p = 0.76) and progression-free survival (p = 0.53). Based on adjusted multivariate Cox proportional hazard analysis, the association between capsular location and disease progression was nonsignificant (all p > 0.05). CONCLUSION: This study demonstrates that the short-term outcomes of RFA for capsular-located PTMCs are comparable to those of noncapsular-located PTMCs. These findings indicate that RFA may be a viable and effective alternative for eligible patients with solitary capsular-located PTMC. CLINICAL RELEVANCE STATEMENT: Radiofrequency ablation may serve as a safe and effective alternative treatment method for eligible patients with capsular-located and noncapsular-located papillary thyroid microcarcinoma. KEY POINTS: • The safety and efficacy of radiofrequency ablation for capsular-located and noncapsular-located papillary thyroid microcarcinomas were comparable. • Disease progression did not differ significantly between capsular-located and noncapsular-located papillary thyroid microcarcinomas. • The incidence of complications for capsular-located papillary thyroid microcarcinoma was low.

Radiofrequency ablation for papillary thyroid microcarcinoma with a trachea-adjacent versus trachea-distant location.

OBJECTIVE: To evaluate the outcomes of radiofrequency ablation (RFA) for papillary thyroid microcarcinoma (PTMC) adjacent to the trachea and compare them with those of PTMC distant from the trachea. METHODS: Patients who received RFA for solitary low-risk PTMC between June 2014 and July 2020 were reviewed and classified into adjacent and distant groups. To balance between-group confounders, the propensity score matching approach was employed. Volume, volume reduction ratio (VRR), tumor disappearance, complications, and disease progression were assessed and compared between the groups. Furthermore, factors affecting disease progression were evaluated. RESULTS: A total of 122 and 470 patients were included in the adjacent and distant groups, respectively. Overall VRR was 99.5% ± 3.1 and cumulative tumor disappearance rate was 99.4% after a mean follow-up time of 40.1 months ± 16.2. Overall disease progression and complications incidence were 3.7% and 1.0%, respectively. No substantial differences were observed between the two groups in the latest volume (0.8 mm3 ± 4.1 vs. 0.9 mm3 ± 4.2, p = .77), VRR (99.7% ± 1.6 vs. 99.5% ± 2.7, p = .75), cumulative tumor disappearance rate (92.6% vs. 94.2%, p = .58), and incidence of disease progression (4.1% vs. 4.5%, p = .70) and complication (1.7% vs. 0.8%, p = .86) after 1:2 matching. Additionally, tracheal adjacency exhibited no association with disease progression in multivariate Cox regression analysis (p = .73). CONCLUSION: For eligible patients with PTMC located adjacent to or distant from the trachea, RFA may offer a safe and effective alternative treatment method.

Long-term Outcomes of Ultrasound-guided Thermal Ablation for the Treatment of Solitary Low-risk Papillary Thyroid Microcarcinoma: A Multicenter Retrospective Study.

OBJECTIVE: To report more than 5-year outcomes of ultrasound-guided thermal ablation (TA) for patients with solitary low-risk papillary thyroid microcarcinoma (PTMC) in a large multicenter cohort. BACKGROUND: TA, including radiofrequency ablation (RFA) and microwave ablation (MWA) have been used in patients with low-risk PTMC who refuse surgery or active surveillance. However, its clinical value remains controversial. MATERIALS AND METHODS: This retrospective multicenter study included 474 patients with solitary low-risk PTMC treated with TA (357 for RFA; 117 for MWA) from 4 centers and followed up for at least 5 years. Disease progression including lymph node metastasis and recurrent tumors, volume reduction rate (VRR), tumor disappearance rate, complications, and delayed surgery were assessed. RFA and MWA outcomes were compared using propensity score matching. RESULTS: During the median follow-up period of 77.2 months, disease progression incidence, lymph node metastasis, and recurrent tumors rates were 3.6%, 1.1%, and 2.5%, respectively. Age below 40 years old, male sex, Hashimoto thyroiditis, and tumor size were not independent factors associated with disease progression by Cox analysis. The median VRR was 100% and 471 tumors disappeared radiographically. Eight patients experienced transient voice change (1.7%) which recovered within 3 months. None of the patients underwent delayed surgery because of anxiety. After 1:1 matching, no significant differences were found in the disease progression, VRR, tumor disappearance rate, or complications between RFA and MWA subgroups. CONCLUSION: This multicenter study revealed that TA was an effective and safe treatment for patients with solitary low-risk PTMC, which could be offered as a treatment option for the management for low-risk PTMC.

Comparison of ultrasound-guided radiofrequency ablation versus thyroid lobectomy for T1bN0M0 papillary thyroid carcinoma.

OBJECTIVE: To investigate and compare the clinical outcomes between radiofrequency ablation (RFA) and thyroid lobectomy (TL) for T1bN0M0 papillary thyroid carcinoma (PTC). METHODS: This retrospective study evaluated 283 patients with solitary T1bN0M0 PTC treated with RFA (RFA group, 91 patients) or TL (TL group, 192 patients) from May 2014 to November 2018. The patients were regularly followed up after treatment. Local tumor progression, lymph node metastasis (LNM), recurrent tumor, persistent tumor, recurrence-free survival (RFS), treatment variables (hospitalization, procedure time, estimated blood loss, and cost), complication, and delayed surgery were compared. RESULTS: During the follow-up (median [interquartile ranges], 50.4 [18.0] months), no significant differences were found in the local tumor progression (4.4% vs 3.6%, p = 1.000), LNM (1.1% vs 2.1%, p = 0.917), recurrent tumor (2.2% vs 1.6%, p = 1.000), persistent tumor (1.1% vs 0%, p = 0.146), and RFS rate (95.6% vs 96.4%, p = 0.816) in the RFA and TL groups. Distant metastasis was not detected. Patients in the RFA group had a shorter hospitalization (0 vs 7.0 [3.0] days, p < 0.001), shorter procedure time (5.6 [2.9] vs 90.0 [38.5] min, p < 0.001), lower estimated blood loss (0 vs 20 [20] mL, p < 0.001), lower cost ($1972.5 [0.1] vs $2362.4 [1009.3], p < 0.001), and lower complication rate (0 vs 12/192 [6.3%], p = 0.015) than those in the TL group. No patients in the RFA group underwent delayed surgery. CONCLUSIONS: This study revealed comparable 4-year clinical outcomes between RFA and TL for T1bN0M0 PTC in terms of local tumor progression and RFS. As a minimally invasive modality, RFA may be a promising feasible alternative to surgery for the treatment of T1bN0M0 PTC in selected patients after strict evaluation. KEY POINTS: • No significant difference in local tumor progression and RFS was found between RFA and TL for T1bN0M0 PTC during a median follow-up period of 50.4 months. • Compared with TL, RFA led to a shorter hospitalization, lower estimated blood loss, lower cost, and lower complication rate. • RFA may be a promising feasible alternative to surgery for the treatment of T1bN0M0 PTC in selected patients after strict evaluation.

Clinical value of artificial intelligence in thyroid ultrasound: a prospective study from the real world.

OBJECTIVE: To evaluate the diagnostic performance of a commercial artificial intelligence (AI)-assisted ultrasonography (US) for thyroid nodules and to validate its value in real-world medical practice. MATERIALS AND METHODS: From March 2021 to July 2021, 236 consecutive patients with 312 suspicious thyroid nodules were prospectively enrolled in this study. One experienced radiologist performed US examinations with a real-time AI system (S-Detect). US images and AI reports of the nodules were recorded. Nine residents and three senior radiologists were invited to make a "benign" or "malignant" diagnosis based on recorded US images without knowing the AI reports. After referring to AI reports, the diagnosis was made again. The diagnostic performance of AI, residents, and senior radiologists with and without AI reports were analyzed. RESULTS: The sensitivity, accuracy, and AUC of the AI system were 0.95, 0.84, and 0.753, respectively, and were not statistically different from those of the experienced radiologists, but were superior to those of the residents (all p < 0.01). The AI-assisted resident strategy significantly improved the accuracy and sensitivity for nodules ≤ 1.5 cm (all p < 0.01), while reducing the unnecessary biopsy rate by up to 27.7% for nodules > 1.5 cm (p = 0.034). CONCLUSIONS: The AI system achieved performance, for cancer diagnosis, comparable to that of an average senior thyroid radiologist. The AI-assisted strategy can significantly improve the overall diagnostic performance for less-experienced radiologists, while increasing the discovery of thyroid cancer ≤ 1.5 cm and reducing unnecessary biopsies for nodules > 1.5 cm in real-world medical practice. KEY POINTS: • The AI system reached a senior radiologist-like level in the evaluation of thyroid cancer and could significantly improve the overall diagnostic performance of residents. • The AI-assisted strategy significantly improved ≤ 1.5 cm thyroid cancer screening AUC, accuracy, and sensitivity of the residents, leading to an increased detection of thyroid cancer while maintaining a comparable specificity to that of radiologists alone. • The AI-assisted strategy significantly reduced the unnecessary biopsy rate for thyroid nodules > 1.5 cm by the residents, while maintaining a comparable sensitivity to that of radiologists alone.

Rigorous radiofrequency ablation can completely treat low-risk small papillary thyroid carcinoma without affecting subsequent surgical management.

OBJECTIVE: Minimally invasive therapies are gaining interest because of the indolence and excellent prognosis of low-risk papillary thyroid carcinoma (PTC). This study aimed to evaluate the outcomes of radiofrequency ablation (RFA) for low-risk PTC and to determine the effects of ablation on subsequent surgical management. METHODS: A medical record review was conducted including patients with low-risk PTC who underwent surgery after RFA from July 2015 to July 2021. Demographic characteristics, tumor characteristics, ablation procedures, surgical findings, and pathological changes were reviewed for all patients. The primary outcomes were surgical and pathological changes in post-ablation patients. RESULTS: Of the 10 patients with 11 PTCs, 9 (90%) were women; the median (SD) patient age was 41.5 (8.2) years. The maximum diameter range of PTCs was 3.0-12.0 mm. All 10 patients underwent rigorous RFA procedure involving a four-step approach, and had received surgical management. Intraoperatively, no patients had muscle and nerve injuries, and mild adhesion of the post-ablation lesions with the anterior cervical muscle was observed in two cases. Histopathologically, no residual PTCs were observed in the ablated areas in all patients. Central lymph node metastasis (LNM) was found in three (30.0%, pN1a). Occult PTCs were observed in three cases (30.0%). CONCLUSIONS: Our findings suggest that low-risk small PTCs can be completely treated with rigorous RFA, which does not affect subsequent surgical management, if necessary. RFA may be a treatment option, but occult PTCs and clinically negative LNMs may be overlooked. Long-term follow-up data are necessary to further identify its efficacy. KEY POINTS: • RFA can completely treat low-risk small PTC. • RFA does not affect the subsequent surgical management if necessary. • Because occult PTCs and clinically negative LNMs may be overlooked by RFA, long-term follow-up data are necessary to further identify its efficacy.

Ultrasound-guided microwave ablation combined with ethanol injection for the treatment of solitary nodular retrosternal goiter: a prospective study of 72 patients.

OBJECTIVES: We prospectively evaluated the efficacy and safety of microwave ablation (MWA) combined with ethanol injection (EI) in solitary nodular retrosternal goiters (RSGs). METHODS: From November 2018 to November 2020, 72 patients diagnosed with solitary nodular RSG were treated by ultrasound-guided MWA with EI. Patients were followed up at 1, 3, 6, and 12 months and every 6-12 months thereafter by ultrasound and contrast-enhanced ultrasound (CEUS). The nodule volume, volume reduction ratio (VRR), neck circumference, symptom score, and cosmetic grading score were recorded to evaluate the treatment efficacy. RESULTS: All patients successfully underwent treatment. The mean initial nodule volume was 71.25 mL ± 61.61 mL, which decreased significantly to 7.47 mL ± 9.19 mL at a mean follow-up time of 23.89 months ± 7.66 months (range 15-39 months) with a mean VRR of 90.99% ± 7.52%. The neck circumference, symptom score, and cosmetic grading score significantly decreased from 36.94 cm ± 3.04 cm to 35.06 cm ± 2.84 cm, from 3.78 ± 1.19 to 0.36 ± 0.63, and from 3.42 ± 0.76 to 1.13 ± 0.37, at the 12 months after treatment, respectively (all 7 p < 0.001). Of all the nodules, eight (11.1%) received a second ablation. No major complications occurred. CONCLUSION: Ultrasound-guided MWA combined with EI is an effective and safe treatment for solitary nodular RSG and may be a potential alternative to surgery in selected patients, especially for those who are ineligible or unwilling to receive surgical treatment. KEY POINTS: • MWA combined with EI is an effective and safe approach for the treatment of solitary nodular RSG. • This treatment should be conducted by experienced physicians. • It provides a potential alternative to surgery for solitary nodular RSG in patients who are ineligible or unwilling to receive surgical treatment.

Single-plane versus real-time biplane approaches for ultrasound-guided central venous catheterization in critical care patients: a randomized controlled trial.

BACKGROUND: Critical care patients often require central venous cannulation (CVC). We hypothesized that real-time biplane ultrasound-guided CVC would improve first-puncture success rate and reduce mechanical complications. The purpose of this study was to compare the success rate and safety of single-plane and real-time biplane approaches for ultrasound-guided CVC. METHODS: From October 2022 to March 2023, 256 participants with critical illness requiring CVC were randomized to either the single-plane (n = 128) or biplane (n = 128) ultrasound-guided cannulation groups. The success rate, number of punctures, procedure duration, incidence of catheterization-related complications, and confidence score of operators were documented. RESULTS: The central vein was successfully cannulated in all 256 participants (163 [64%] man and 93 [36%] women; mean age 69 ± 19 [range 13-104 years]), including 182 and 74 who underwent internal jugular vein cannulation (IJVC) and femoral vein cannulation (FVC), respectively. The incidence of successful puncture on the first attempt was higher in the biplane group than that in the single-plane group (91.6% vs. 74.7%; relative risk (RR), 1.226; 95% confidence interval (CI), 1.069-1.405; P = 0.002 for the IJVC and 90.9% vs. 68.3%; RR, 1.331; 95% CI, 1.053-1.684; P = 0.019 for the FVC). The biplane group was also associated with a higher first-puncture single-pass catheterization success rate (87.4% vs. 69.0% and 90.9% vs. 68.3%), fewer undesired punctures (1[1-1(1-2)] vs. 1[1-2(1-4)] and 1[1-1(1-3)] vs. 1[1-2(1-4)]), shorter cannulation time (205 s [162-283 (66-1,526)] vs. 311 s [243-401 (136-1,223)] and 228 s [193-306 (66-1,669)] vs. 340 s [246-499 (130-944)]), and fewer immediate complications (10.5% vs. 28.7% and 9.1% vs. 34.1%) for both IJVC and FVC (all P < 0.05). CONCLUSION: Real-time biplane imaging of ultrasound-guided CVCs offers advantages over the single-plane approach for critically ill patients. TRIAL REGISTRATION: This prospective RCT was registered at Chinese Clinical Trial Registry (ChiCTR2200064843). Registered 19 October 2022.

Optimal thyrotropin level for low-risk papillary thyroid carcinoma after ultrasound-guided radiofrequency ablation.

PURPOSE: Maintaining an optimal thyroid stimulating hormone (TSH) level is important in the postoperative management of papillary thyroid carcinoma (PTC). However, there is little evidence for TSH target levels in patients undergoing radiofrequency ablation (RFA). This study aimed to determine the optimal TSH level for management in low-risk patients who underwent RFA. METHODS: This retrospective propensity score-matched cohort study included patients with low-risk PTC who underwent RFA from January 2014 to December 2018. The patients were categorized into two groups based on the range of TSH levels: low (≤2 mU/L) and high (>2 mU/L) TSH levels. Local tumor progression and disease-free survival (DFS) were compared between the low TSH and high TSH groups, using propensity score analyses based on patient- and tumor-level characteristics. Univariate analyses were performed to select risk factors for tumor progression. RESULTS: Overall, our study included 516 patients with low-risk PTC who underwent RFA with a long-term follow-up of 5-years. During follow-up, the overall incidence rate of local tumor progression was 4.8% (25/516), with no significant difference between the matched groups (7/106 [6.6%] vs. 5/53 [9.4%], p = 0.524). DFS did not differ between the two groups (p = 0.5). Moreover, TSH level was not regarded as a significant predictor of tumor progression after Cox analysis; primary tumor size was the only relevant risk factor. CONCLUSION: This large propensity-matched study revealed no association between TSH levels and tumor progression. Thus, for patients with low-risk PTC who underwent RFA, the optimalTSH level is recommended at the euthyroid range.

Long-term results of radiofrequency ablation for locally recurrent papillary thyroid carcinoma.

OBJECTIVE: To evaluate the long-term efficacy and safety of ultrasound-guided radiofrequency ablation (RFA) for treating locally recurrent papillary thyroid cancer (PTC). METHODS: This retrospective study involved 32 patients with pathologically confirmed locally recurrent PTC. The ablation zone was assessed by contrast-enhanced ultrasound (CEUS) after RFA. At baseline, 6 and 12 months and every 6 months or 12 months thereafter, the following results were recorded: recurrence rate, largest diameter, volume, volume reduction rate (VRR) of recurrent lesions, serum thyroglobulin (Tg) level and complications. RESULTS: 58 recurrent lesions in 32 patients were successfully ablated with RFA. The mean follow-up time was 73.19 ± 12.68 months (range, 60 to 98 months). At the last follow-up, almost all ablated lesions disappeared completely, and only one lesion showed scar-like changes. Nine (28.13%) patients developed new locally recurrent tumors; they were successfully treated with repeat RFA sessions. No new recurrent lesions were found during the follow-up. The largest diameter and volume of recurrent lesions decreased from 13.71 ± 6.48 mm and 520.43 ± 627.85 mm3 to 0 each at the end of observation period (p < .001). The average VRRs at 6, 12, 24, 36, 48, 60 months and last follow-up after RFA were 54.17%, 72.90%, 82.28%, 89.30%, 92.57%, 96.60%, 96.88%, 98.14% and 100% respectively. The median of serum Tg level was decreased from 1.48 ng/mL to 0.00 ng/mL (p < .05). No complications were reported during the follow-up. CONCLUSIONS: US-guided RFA is an effective and safe option for treating locally recurrent PTC in selected patients, with favorable long-term outcomes.

Radiofrequency ablation for papillary thyroid cancer located in isthmus: comparison with that originated in thyroid lobe.

PURPOSE: To analyze the outcomes of radiofrequency ablation (RFA) for isthmus papillary thyroid cancer (PTC) versus PTC originating from the lobes. METHODS: Patients with solitary low-risk PTC treated with RFA between July 2014 and December 2019 were retrospectively reviewed. This study was approved by our institutional review board. Of the 562 patients, 104 and 458 had PTCs located in the thyroid isthmus and thyroid lobes, respectively. Local tumor progression (LTP), LTP-free survival (LTPFS), changes in tumor volume, and complications were compared between the two groups using propensity-score matching (PSM). RESULTS: The isthmic and lobar groups showed no significant differences in LTP (2.9% vs. 3.8%), new PTC (2.9% vs. 2.9%), persistent lesions (0.0% vs. 0.2%), or LTPFS after PSM. Before PSM, the two groups showed significant differences in the volume reduction ratio (VRR) of the ablated tumors at 1, 3, 24, 30, and 48 months after RFA, but no differences between the two groups were observed in tumor volume, VRR, or disappearance rate after PSM (p > .05). One patient in the isthmic group presented with coughing, while another complained of hoarseness. Complications did not differ significantly between the two groups (p > .05). CONCLUSIONS: The outcomes of RFA for patients with low-risk PTC in the thyroid isthmus and thyroid lobes were similar. Therefore, RFA may serve as an alternative treatment option for patients with low-risk isthmic PTC.

[Research Progress in the Application of Ultrasound-Guided Robot in Minimally Invasive Surgery].

With the continuous advances in modern medical technology and equipment,minimally invasive surgery (MIS) is widely applied in clinical practice.Ultrasound (US) as a real-time,portable,and radiation-free medical imaging method can be used for the intraoperative guidance in MIS to ensure safe and effective surgery.However,the physical characteristics of conventional US fail to display some tissue structures of the human body due to the existence of gas and bone.US-based navigation can make up for the deficiencies by advanced imaging technologies including spatial orientation,image reconstruction,and multi-modality image fusion,being real-time,accurate,and radiation-free.Therefore,US-guided robots can achieve safe,effective,and minimally invasive operation in MIS.This paper reviews the studies of US-guided robots in MIS and prospects the development of this field.

[Research Status and Prospect of New Ultrasound Technology in Predicting Cervical Lymph Node Metastasis of Thyroid Papillary Carcinoma].

Papillary thyroid carcinoma (PTC) is the most common pathological type of thyroid cancer,accounting for 90%.Most cases of PTC are inert tumors,while a few are invasive.Cervical lymph node metastasis is one of the major manifestations of invasive PTC.Preoperative accurate prediction of cervical lymph node metastasis is of great significance for the selection of therapeutic regimen and the evaluation of prognosis.New ultrasound technology is a non-invasive,convenient,and radiation-free examination method,playing a key role in predicting the cervical lymph node metastasis of PTC.This paper reviews the research status and makes an outlook on new ultrasound technology in predicting cervical lymph node metastasis of PTC.

[Advances in Molecular Targeted Ultrasound Contrast Agents].

In real-time ultrasound,molecular targeted contrast agent is introduced into the blood circulation through peripheral intravenous injection to enhance the imaging signal of target lesions after binding to the corresponding intravascular receptors,which can realize early diagnosis,staging of diseases,assessment of treatment response,and targeted treatment.In addition,molecular targeted ultrasound contrast agents provide a platform for the delivery of drugs and genes via microbubbles,and nanoscale contrast agents can be infiltrated through vascular endothelium into the interstitial space of the lesion for imaging or treatment.The available studies of molecular targeted ultrasound contrast agents mainly focus on the preclinical trials.Some clinical trials have been conducted in humans and preliminarily confirm the safety and feasibility of targeted ultrasound contrast agents.The molecular targeted ultrasound contrast agents enjoy a broad prospect in clinical application.

[Effect of Calcification on the Ultrasound-Guided Radiofrequency Ablation of Papillary Thyroid Carcinoma].

Objective To investigate the effect of calcification on the ultrasound-guided radiofrequency ablation(RFA)of papillary thyroid carcinoma(PTC).Methods We retrospectively analyzed the preoperative and follow-up data of 164 patients(182 nodules)with PTC treated by percutaneous ultrasound-guided RFA in the First Medical Center of Chinese PLA General Hospital from January 1,2018 to December 31,2021.The tumor status 12 months after RFA was taken as the endpoint event.The univariate Logistic regression analysis was employed to predict the influencing factors of incomplete ablation.The factors were then included in the multivariate Logistic regression analysis for prediction of the independent risk factors of incomplete ablation.Results The maximum nodule diameter(OR=1.16,95%CI=1.04-1.29,P=0.009)and calcification ratio >2/3(OR=19.27,95%CI=4.02-92.28,P<0.001)were the factors influencing the disappearance of lesion 12 months after RFA.Conclusions PTC with calcification can be treated with ultrasound-guided RFA.In the case of calcification ratio ≤ 2/3,this therapy demonstrates the effect equivalent to that of no calcification.

Clinical outcomes of radiofrequency ablation for multifocal papillary thyroid microcarcinoma versus unifocal papillary thyroid microcarcinoma: a propensity-matched cohort study.

OBJECTIVE: To investigate and compare the clinical outcomes of radiofrequency ablation (RFA) for multifocal papillary thyroid microcarcinoma (PTMC) versus unifocal PTMC in a large cohort. METHODS: Patients with low-risk PTMC (n = 487) who underwent RFA were included in this retrospective study and divided into the unifocal group (U group) (n = 432) and the multifocal group (M group) (n = 55) according to the number of lesions. After 1:1 propensity score matching (PSM), volume, volume reduction ratio (VRR), the development of local tumor progression including lymph node metastasis (LNM), recurrent PTMC and persistent lesions, and recurrence-free survival (RFS) rate were evaluated and compared between the two groups. The different impacts of multifocality on recurrence after RFA for PTMC were investigated by Cox analysis. RESULTS: During a mean follow-up time of 49.25 ± 12.98 months, the overall VRR was 99.40 ± 4.43% and the overall incidence of local tumor progression was 3.70% (18/487). No complications occurred after RFA. After PSM, no significant differences were found in volume (0.11 ± 0.69 mm3 vs 0 mm3, p = 0.441), VRR (99.87 ± 0.78% vs 100%, p = 0.441), complete disappearance rate (95.61% vs 89.09%, p = 0.201), incidence of local tumor progression (5.45% vs 5.45%, p = 1.000), LNM (1.82% vs 0%, p = 0.317), recurrent PTMC (1.82% vs 5.45%, p = 0.611), persistent lesions (1.82% vs 0%, p = 0.317), and RFS rate (96.36% vs 94.55%, p = 0.632) between the M group and U group. The association between multifocality and local tumor recurrence also remained nonsignificant (p = 0.619). No distant metastasis or delayed surgery occurred. CONCLUSIONS: The impact of multifocality on the prognosis after RFA for low-risk PTMC was little. RFA might be a promising treatment for both unifocal and multifocal PTMC in properly selected patients after sufficient preoperative evaluation. KEY POINTS: • No significant differences are found in the local tumor progression between the unifocal PTMC and multifocal PTMC. • Multifocality is not associated with higher recurrence after RFA for low-risk PTMC. • RFA is a promising alternative for both unifocal and multifocal PTMC.

Differential diagnosis and feature visualization for thyroid nodules using computer-aided ultrasonic diagnosis system: initial clinical assessment.

BACKGROUND: To assess the diagnostic efficacy of the computer-aided ultrasonic diagnosis system (CAD system) in differentiating benign and malignant thyroid nodules. METHODS: The images of 296 thyroid nodules were included in validation sets. The diagnostic efficacy of the CAD system was compared with that of junior physicians and senior physicians, as well as that of the combination diagnosis of the CAD system with junior physicians. The diagnostic efficacy of the CAD system for different sizes of thyroid nodules was compared. RESULTS: The diagnostic sensitivity and accuracy of the CAD system were higher than those of junior physicians (83.4% vs. 72.2%, 73.0% vs. 69.6%), but the diagnostic specificity of the CAD system was lower than that of junior physicians (62.1% vs. 66.9%). The diagnostic accuracy of the CAD system was lower than that of senior physicians (73.0% vs. 83.8%). However, the combination diagnosis of the CAD system with junior physicians had higher accuracy (81.8%) and AUC (0.842) than those of either the CAD system or junior physicians alone, and comparable diagnostic performance with those of senior physicians. The Kappa was 0.635 in the combination diagnosis of the CAD system with junior physicians, showing good consistency with the pathological results. The accuracy (76.4%) of the CAD system was the highest for nodules of 1-2 cm. CONCLUSION: The CAD system can effectively assist physicians to identify malignant and benign thyroid nodules, reduce the overdiagnosis and overtreatment of thyroid nodules, avoid unnecessary invasive fine needle aspiration, and improve the diagnostic accuracy of junior physicians.

Targeting Diagnosis of High-Risk Papillary Thyroid Carcinoma Using Ultrasound Contrast Agent With the BRAFV600E Mutation: An Experimental Study.

OBJECTIVE: High-risk papillary thyroid carcinoma (PTC) patients with BRAF mutation have lymph node and distant metastases and poor prognosis. Therefore, this study aims to develop a targeted ultrasound contrast agent for the BRAFV600E mutation to screen high-risk PTC at early stage. METHODS: The targeted lipid nanobubbles carrying BRAFV600E antibody were prepared using thin film hydration-sonication and avidin-biotin binding methods. The physicochemical properties and stability of the targeted nanobubbles were detected by transmission electron microscopy, atomic force microscopy, and confocal laser scanning microscopy. The target binding abilities of the targeted nanobubbles in the PTC cells (B-CPAP) overexpressed mutant BRAFV600E were evaluated by immunofluorescence staining, quantitative real-time polymerase chain reaction, western blot, and fluorescence microscopy. After PTC tumor models overexpressed mutant BRAFV600E were established, the enhanced images of targeted lipid nanobubbles and untargeted lipid nanobubbles on PTC tumors in nude mice were observed using contrast-enhanced ultrasound imaging. RESULTS: The targeted lipid nanobubbles revealed uniform, round morphology, and good stability with a nanoscale size. Besides, BRAFV600E monoclonal antibody was observed to be combined on the surface of lipid nanobubbles. Furthermore, the targeted nanobubbles had a good targeting diagnosis ability in PTC cells with BRAFV600E overexpression. Moreover, the targeted nanobubbles had better ultrasound enhancement and peak intensity of the time-intensity curve (P < .001) in PTC tumors with BRAFV600E overexpression as compared to the untargeted lipid nanobubbles. CONCLUSION: The targeted lipid nanobubbles carrying BRAFV600E antibody could be regarded as a potential targeted ultrasound contrast agent for the diagnosis of high-risk PTC.